Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

1,249 results found
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Febrile infection-related epilepsy syndrome (FIRES)

Febrile infection-related epilepsy syndrome (FIRES) is a severe postinfectious neurological disorder that presents with status epilepticus in a previously normal child (or less commonly adult) after a febrile illness. In these cases, pleocytosis or elevated protein levels on CSF has been report...
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Feingold syndrome

Feingold syndrome is characterized by the combination of: microcephaly digital abnormalities alimentary tract atresias especially esophageal atresia
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Femoral facial syndrome

Femoral facial syndrome, also known as femoral hypoplasia-unusual facies syndrome, is a rare congenital syndrome characterized by varying degrees of femoral hypoplasia and facial dysmorphism 1. Clinical presentation Femoral facial syndrome can cause varying degrees of femoral malformation rang...
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Femur sparing intrauterine growth restriction

Femur sparing intrauterine growth restriction is considered by some authors as a particular type of intrauterine growth restriction (IUGR) 1. In this type, the femoral length is the only standard fetal biometric parameter unaffected while all others are reduced.
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Fetal circulation

Fetal circulation differs from the adult circulation due to the presence of certain vessels and shunts.  These shunts close after birth, and most of the fetal vessels are visible as remnants in the adult circulation. The function of these shunts is to direct oxygen-rich venous blood to the syst...
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Fetal complete atrioventricular block

Fetal congenital complete heart block (CAVB) is a rare cardiac conduction abnormality that is associated with high morbidity and mortality. It is considered the commonest of fetal bradyarrhymias. Epidemiology The estimated prevalence of complete heart block in newborns is at ~1 in 20,000. Pat...
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Fetal lung interstitial tumor

Fetal lung interstitial tumor (FLIT) is a recently proposed designation for a rare primary lung mass detected prenatally or when the patient is up to 3 months old. Epidemiology Fetal lung interstitial tumors have a slight predominance in boys 1. Pathology Fetal lung interstitial tumors were ...
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Fetal orbital masses

A fetal orbital mass is a rare occurrence but can arise from many patholologies  The list includes Tumourous orbital masses fetal retinoblastoma fetal orbital teratoma Non tumourous orbital masses orbital encephalocoele 2 orbital heterotopic brain tissue 1 congenital cystic eyeball 4
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Fetal tricuspid regurgitation

Tricuspid regurgitation (TR) (also known as tricuspid insufficiency) is a common finding in imaging of the fetus. Tricuspid regurgitation represents the abnormal backflow of blood into the right atrium during right ventricular contraction due to valvular leakage (i.e. it is a valvulopathy).  Ep...
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Fetal tumors

Although rare, a number of tumors may be diagnosed antenatally. These fetal tumors are a diverse and a unique group of conditions, and include: neuroblastoma: most common tumor overall teratomas sacrococcygeal teratoma head and neck teratoma/epignathus mediastinal teratoma intrapericardial...
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Fetus in fetu

Fetus-in-fetu is an extremely rare abnormality that occurs secondary to abnormal embryogenesis in a monochorionic diamniotic pregnancy where a non-viable fetus becomes enclosed within a normally developing fetus. Epidemiology Fetus-in-fetu is very rare, with an incidence of 1/500,000 live birt...
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Fibrodysplasia ossificans progressiva

Fibrodysplasia ossificans progressiva (FOP), previously known as myositis ossificans progressiva (MOP) and also known as Munchmeyer’s disease, is a rare, inherited disorder characterized by progressive fibrosis and ossification of muscles, tendons, fasciae, aponeuroses, and ligaments of multiple...
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Fibromatosis colli

Fibromatosis colli is a rare form of infantile fibromatosis that occurs within the sternocleidomastoid muscle. Epidemiology There may be a slight male predilection. It typically presents a few weeks after birth. Clinical presentation Presentation is usually with torticollis and is most frequ...
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Fibrosing colonopathy

Fibrosing colonopathy a condition characterized by progressive submucosal fibrosis, particularly of the proximal colon. It is associated with high dose lipase supplementation used to treat exocrine insufficiency of the pancreas, such as in treatment for cystic fibrosis. Epidemiology It is more...
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Fibrous cortical defect

Fibrous cortical defects (FCD) are benign bony lesions and are a type of fibroxanthoma, histologically identical to the larger non-ossifying fibroma (NOF). Epidemiology Fibrous cortical defects typically occur in children (usually 2-15 years), and indeed are one of the most common benign bony ...
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Fibrous dysplasia

Fibrous dysplasia (FD) is a non-neoplastic tumor-like congenital process, manifested as a localized defect in osteoblastic differentiation and maturation, with the replacement of normal bone with large fibrous stroma and islands of immature woven bone. Fibrous dysplasia has a varied radiographic...
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Fibrous hamartoma of infancy

Fibrous hamartoma of infancy is a rare benign tumor of the subcutaneous tissues seen in children. More than 90% of cases present in the first year of life with up to 25% being congenital 1. Epidemiology There is a reported male:female ratio of 2:1 but the exact incidence is unknown 2. Clinica...
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Fibroxanthoma of bone

Fibroxanthoma of bone is a confusing term that is sometimes used to encompass non-ossifying fibroma and fibrous cortical defect, and at other times synonymously with just non-ossifying fibromas. As non-ossifying fibroma and fibrous cortical defect are histologically the same, and differ only in ...
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Fibular hemimelia

Fibular hemimelia is a congenital lower limb anomaly characterized by partial or complete absence of the fibula and includes a spectrum ranging from mild fibular hypoplasia to complete fibular aplasia 1. Epidemiology Although rare in occurrence, it is the most common congenital absence of long...
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Filar cyst

A filar cyst is an incidental finding on neonatal lumbar sonography located in the filum terminale of the spinal cord. It is considered a normal variant and is often confused for a ventriculus terminalis, a smooth dilated cavity of the central canal, located within the conus medullaris. The inc...
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Filling defect

A filling defect is a general term used to refer to any abnormality on an imaging study which disrupts the normal opacification (filling) of a cavity or lumen. The opacification maybe physiological, for example, bile in the gallbladder or blood in a dural venous sinus, or maybe due to the instal...
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Finger series (pediatric)

The f​inger series for pediatrics often consist of a posteroanterior and lateral view only in order to minimize radiation dose to the patient. Depending on the department and clinical indication, an additional oblique view may also be done. Indications trauma with suspected fracture suspected...
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Five Ts of cyanotic congenital heart disease (mnemonic)

A mnemonic to remember the most important congenital heart defects associated with cyanosis is: 5 Ts Mnemonic T: tetralogy of Fallot (TOF) T: transposition of the great arteries (TGA) T: truncus arteriosus T: total anomalous pulmonary venous return (TAPVR) T: tricuspid valve abnormalities...
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Flat floor of fourth ventricle sign

The flat floor of fourth ventricle sign is useful in detecting a pontine mass and is a sign of mass effect. The normal floor of the fourth ventricle (remember that the floor is anterior) normally slopes upwards towards the midline, with the facial colliculi visible on either side.  It is a non-...
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Focal periphyseal edema zone

Focal periphyseal edema zones, also known as FOPE zones, are regions of bone marrow edema seen on MRI that are principally located at the physes about the knee. They are thought to represent potentially painful manifestations of physiologic physeal fusion 1. Epidemiology FOPE zones are seen in...
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Fontanelle

Fontanelles are the soft membraneous regions of the fetus and neonate calvarium where the corners of three or four developing flat bones meet and allow for the growth over the skull over the developing brain. There are two main, palpable fontanelles in the midline: anterior fontanelle, the lar...
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Foot (weightbearing lateral view)

The weightbearing lateral foot radiograph is important in the assessment of foot alignment and the diagnosis of abnormalities that cause malalignment and foot pain. Nonweightbearing views (e.g. lateral foot) would be inadequate for the assessment of alignment as the bones of the feet are not in ...
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Foramen ovale (cardiac)

The foramen ovale (or ovalis) is the opening in the interatrial septum in the fetal heart that allows blood to bypass the right ventricle and non-ventilated lungs, shunted from the right atrium to the left atrium. Specifically it represents the opening between the upper and lower portions of the...
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Forearm fracture

Forearm fractures are a group of fractures that occur in the forearm following trauma. The radius and ulna are bound together at the proximal and distal radioulnar joints and act as a ring. Like elsewhere in the body, it is difficult to only fracture one bone if there is a bony ring. If the radi...
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Forearm series (pediatrics)

The forearm series for pediatrics comprises an anteroposterior and lateral projection. These projections examine the entire radius and ulna including the distal and proximal articulations. Indications Forearm x-rays are indicated for a variety of settings including: trauma bony tenderness s...
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Foreign body ingestion series (pediatric)

The suspected foreign body ingestion series is a set of radiographs utilized to detect and identify foreign bodies in the gastrointestinal tract. It involves an AP and lateral radiograph of the neck, chest, and abdomen ensuring adequate coverage of the entire gastrointestinal tract 1. Patient p...
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Foreign body inhalation series (pediatric)

The suspected foreign body inhalation series although not a primary port of investigation aims to detect and identify both foreign bodies or the secondary signs of inhaled foreign bodies 1. It involves a frontal chest radiograph in both the inspiration and expiratory phases and, in some cases, b...
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Fossa ovale

The fossa ovale (or ovalis) is the small oval depression in the interatrial septum at the site of the closed foramen ovale, which closes once fetal circulation ceases in the first few minutes of postnatal life. It represents the overlapping primary and secondary septa of the interatrial septum. ...
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Fountain sign (acute idiopathic scrotal edema)

The fountain sign is a sonographic sign described in acute idiopathic scrotal edema (AISE). It refers to the appearance of the pattern of vascularity seen during transverse color Doppler sonography of the scrotum with both testes together 1. In this transverse view, in patients with AISE, marke...
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Fourth ventriculocoele

A fourth ventriculocoele is large posterior fossa cyst which remodels, thins and eventually erodes through the occipital bone to form an occipital encephalocoele. It may be classified as part of the Dandy-Walker continuum, but this is controversial.
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Fowler syndrome

Fowler syndrome, also known as proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome (PVHH), is a rare inherited condition. Terminology Not to be confused with Fowler syndrome of urinary retention, a condition caused by primary failure of urethral sphincter relaxation resulting ...
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F P Weber syndrome

F P Weber syndrome (FPWS) is a traditional eponymous denomination of a certain type of angiodysplasia, that would nowadays rather be called a mixed hemolymphatic congenital vascular malformation (CVM) with arteriovenous (AV) shunting, based on the Hamburg classification of CVMs. In his original...
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Fracture translation

Fracture translation (also called translocation) describes the movement of fractured bones away from each other. In some cases, people will just use the term displacement to describe translation. However, displacement should really be used as a broad term that refers to angulation, translation a...
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Fragile X syndrome

Fragile X syndrome is the most common inherited cause of cognitive disability and is the result of the mutation in the fragile X mental retardation 1 (FMR1) gene.  Epidemiology Although the degree of cognitive disability is typically more severe in males with fragile X syndrome, females can al...
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Fraser syndrome

Fraser syndrome is an extremely rare congenital syndromic anomaly.  Epidemiology The estimated incidence is at around 0.04:10,000 live-born infants and 1:10,000 stillbirths. Clinical spectrum The syndromic spectrum can comprise of: cryptophthalmos syndactyly: often cutaneous tracheal atre...
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Freiberg disease

Freiberg disease, also known as Freiberg infraction, is osteochondrosis of metatarsal heads. It typically affects the 2nd metatarsal head, although the 3rd and  4th may also be affected. It can be bilateral in up to 10% of cases. Epidemiology It is most common in females aged 10-18 years (male...
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Frontal bossing

Frontal bossing is a calvarial radiographic feature where the front of the skull appears protruding anteriorly. It is best appreciated on a sagittal or lateral image. Pathology This feature can be seen in many conditions (in alphabetical order): 18q syndrome acromegaly achondroplasia ß-tha...
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Frontonasal dysplasia

Frontonasal dysplasia, also known as median cleft face syndrome, is a rare disorder characterized by midline defects involving the face, head, and central nervous system. Epidemiology Frontonasal dysplasia is considered to be a very rare condition, with approximately 100 cases having been repo...
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Frykman classification of distal radial fractures

The Frykman classification of distal radial fractures is based on the AP appearance and encompasses the eponymous entities of Colles fracture, Smith fracture, Barton fracture, chauffeur fracture. It assesses the pattern of fractures, involvement of the radioulnar joint and presence of a distal u...
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Fucosidosis

Fucosidosis is a rare inherited autosomal recessive lysosomal storage disorder, hypomyelinating disorder, and mucopolysaccharidosis-like disorder, characterized by multiorgan accumulation of fucose-containing products. Epidemiology It is considered very rare, with approximately only 100 cases ...
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Fukuyama congenital muscular dystrophy

Fukuyama congenital muscular dystrophy (FCMD) is a form of congenital muscular dystrophy. Epidemiology FCMD is almost exclusively found in Japan where it has an incidence of 2-4 per 100,000 infants and is the second most common muscular dystrophy after Duchenne muscular dystrophy 1,2. However,...
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Gage sign

The Gage sign is a V-shaped lucent defect at the lateral portion of the epiphysis and/or adjacent metaphysis. It is pathognomonic for Legg-Calve-Perthes disease. It may occur early in the disease and is one of the five indicators of a worse prognosis, which are: Gage sign calcification latera...
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Galeazzi fracture-dislocation

Galeazzi fracture-dislocations consist of fracture of the distal part of the radius with dislocation of distal radioulnar joint and an intact ulna. A Galeazzi-equivalent fracture is a distal radial fracture with a distal ulnar physeal fracture 2. Epidemiology Galeazzi fractures are primarily e...
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Gallbladder ghost triad

Gallbladder ghost triad is a term used on ultrasound studies when there is a combination of three gallbladder features on biliary atresia: atretic gallbladder, length less than 19 mm irregular or lobular contour  lack of smooth/complete echogenic mucosal lining with an indistinct wall The te...
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Galloway-Mowat syndrome

Galloway-Mowat syndrome (GAMOS) is a rare autosomal recessive disorder characterized by nephrotic syndrome and central nervous system (CNS) abnormalities, namely microcephaly. Epidemiology Galloway-Mowat syndrome is considered extremely rare. Approximately 40 cases have been reported worldwide...
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Ganglioglioma

Gangliogliomas are uncommon, usually low-grade, CNS tumors. Epilepsy is a common clinical presentation and this tumor has a typical occurrence in the temporal lobes, although they have been described in all parts of the central nervous system. Their appearance on imaging is very variable: from ...
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Ganglioneuroma

Ganglioneuromas are fully differentiated neuronal tumors that do not contain immature elements and potentially occur anywhere along with the peripheral autonomic ganglion sites.  On imaging, usually, they present as well-defined solid masses and can be quite large at presentation. Generally, th...
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Gardner fibroma

Gardner fibromas are benign fibrous plaque-like soft tissue masses formed by a haphazard arrangement of collagen fibers. Terminology An acceptable alternative term for Gardner fibroma is Gardner associated fibroma, the term desmoid precursor lesion is now discouraged 1. Epidemiology Gardner ...
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Gastric duplication cyst

Gastric duplication cysts are rare congenital foregut duplication cysts affecting the stomach. Gastrointestinal tract duplication cysts (GTDCs) most commonly affect the ileum, followed by the esophagus, large bowel, and jejunum; gastric location accounts for less than 10% of all gastrointestinal...
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Gastric volvulus

Gastric volvulus is a specific type of volvulus that occurs when the stomach twists on its mesentery. It should be at least 180° and cause bowel obstruction to be called gastric volvulus. Merely gastric rotation on its root is not considered gastric volvulus. Epidemiology Organo-axial volvulus...
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Gastro-esophageal reflux disease

Gastro-esophageal reflux disease (GERD) is a spectrum of disease that occurs when gastric acid refluxes from the stomach into the lower end of the esophagus across the lower esophageal sphincter (LES). Epidemiology It affects 10% to 20% of the adult population in the United States and Western ...
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Gastroschisis

Gastroschisis refers to an extra-abdominal herniation (evisceration) of fetal or neonatal bowel loops (and occasionally portions of the stomach and or liver) into the amniotic cavity through a para-umbilical anterior abdominal wall defect.   Epidemiology The estimated incidence is at around 1-...
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Gaucher disease

Gaucher disease (GD) is the most common lysosomal storage disorder in humans. It is an autosomal recessive, multisystem disease arising from a deficiency of glucocerebrosidase or beta-glucosidase activity, resulting in the accumulation of a glycolipid (glucocerebroside) within the lysosomes of m...
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Generalized increased bone density in children

The causes of generalized increased bone density in pediatric patients can be divided according to a broad category of causes: skeletal dysplasias osteopetrosis pyknodysostosis metabolic renal osteodystrophy poisoning lead dense metaphyseal bands cortex and flat bones may also be slight...
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Gerbode defect

The Gerbode defect describes a rare abnormal left-to-right shunt between the left ventricle and right atrium through a defect in the atrioventricular septum, usually congenital in etiology. Epidemiology Gerbode defects are rare congenital cardiac anomalies, and are thought to account for less ...
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Germinal matrix hemorrhage

Germinal matrix hemorrhages, also known as periventricular-intraventricular hemorrhages (PVIH), are the commonest type of intracranial hemorrhage in neonates and are related to perinatal stress affecting the highly vascularized subependymal germinal matrix. The majority of cases occur in prematu...
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Germinal matrix hemorrhage (grading)

Grading of germinal matrix hemorrhage has taken several forms over the years. The most commonly used system is the sonographic grading system proposed by Burstein, Papile, et al.  Classification grade I restricted to subependymal region/germinal matrix which is seen in the caudothalamic groov...
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Ghost vertebra

Ghost vertebra is a sign, that is generally used synonymously with bone-within-a-bone vertebra, and as such, the causes form a subset of those causing bone within a bone appearance 2: Thorotrast administration: bone within a bone appearance due to temporary growth arrest 1 stress line rickets...
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Gillespie syndrome

Gillespie syndrome is a rare genetic condition presenting as a mydriasis, secondary to an omnipresent partial aniridia. The abnormal iris is bilateral, with a highly-specific scalloped inner margin, due to hypoplasia of the central constrictor pupillae fibers. Associated features include an unch...
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Global testicular infarction

Global testicular infarction is fortunately rare, and is most commonly seen in the context of testicular torsion. However rarely it can occur secondary to other causes.  Pathology Etiology testicular torsion epididymo-orchitis 1-4 iatrogenic surgery, e.g. inguinal hernia repair 7 post-EVA...
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Glutaric aciduria type 1

Glutaric aciduria type 1 is a leukodystrophy that can be subclassified as an organic acidopathy. It has a highly variable clinical presentation, and laboratory investigations are not always diagnostic. Imaging, therefore, has an important role to play as the MRI features can be characteristic. ...
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Glycogen storage disease

Glycogen storage disease (GSD) refers to a number of syndromes which are characterized by a defect in synthesis, metabolism or storage of glycogen. Pathology There are many types of GSD: type I: von Gierke disease type II: Pompe disease type III: Cori or Forbes disease type IV: Andersen di...
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Glycogen storage disease type I

Glycogen storage disease type I (GSD-I), also known as von Gierke disease, is a type of glycogen storage disease where there is excess deposition of glycogen primarily in the liver, but also in the kidney and small bowel. Epidemiology It occurs approximately one in every 100,000 live births 2,...
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Glycogen storage disease type II

Glycogen storage disease type II, also known as Pompe disease or acid maltase deficiency disease, is an inherited lysosomal storage disorder characterized by abnormal glycogen accumulation within lysosomes. It is a multisystem disorder involving the heart, skeletal muscle and liver. It is caused...
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GM2 gangliosidoses

The GM2 gangliosidoses are a small group of three closely-related rare genetic conditions, all due to a deficiency of beta-hexosaminidase, an enzyme vital for the metabolism of GM2 gangliosides in lysosomes, especially important in the brain. The GM2 gangliosidoses form a subgroup of the lysosom...
Article

Goldenhar syndrome

Goldenhar syndrome, also known as oculo-auriculo-vertebral spectrum (OAVS), Goldenhar-Gorlin syndrome or facio-auriculo-vertebral dysplasia, is a complex congenital anomaly characterized by abnormalities of the ears, eyes and vertebrae. Epidemiology The estimated incidence is at 1 in 3000-5000...
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Gomez-Lopez-Hernandez syndrome

Gomez-Lopez-Hernandez syndrome, also known as cerebellotrigeminal-dermal dysplasia, is a rare phakomatosis characterized by rhombencephalosynapsis, parietal-occipital scalp alopecia, brachycephaly, facial malformations and trigeminal anesthesia.  History and etymology It is named after Manuel ...
Article

Gonadal dysgenesis

Gonadal dysgenesis refers to a spectrum of anomalies with abnormal development of the gonads. It falls under the even broader group of disorders of gender development. Pathology In many cases, the gonads are replaced by fibrous tissue. Subtypes complete gonadal dysgenesis (CGD) / Swyer syndr...
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Gonadoblastoma

Gonadoblastomas are uncommon sex cord / stromal tumors. They are associated with disorders of sexual development (previously known as "intersex disorders"). Epidemiology The vast majority are found <30 years of age. Most are discovered in the perinatal period. May occur in phenotypic males or ...
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Gracile bones (mnemonic)

The causes of gracile bones can be recalled with the following mnemonic: NIMROD Mnemonic NIMROD N: neurofibromatosis I: immobilization/paralysis M: muscular dystrophy, e.g. Duchenne muscular dystrophy R: rheumatoid arthritis (juvenile RA) O: osteogenesis imperfecta D: dysplasia, e.g. Ma...
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Graf method for ultrasound classification of developmental dysplasia of the hip

The Graf method for ultrasound classification system for developmental dysplasia of the hip (DDH) in infants, combines both alpha and beta angles. There are a number of additional subdivisions, which are often not used clinically.  As a general rule, the alpha angle determines the type and in s...
Article

Greenstick fracture

Greenstick fractures are incomplete fractures of long bones and are usually seen in young children, more commonly less than 10 years of age. They are commonly mid-diaphyseal, affecting the forearm and lower leg. They are distinct from torus fractures. Pathology Mechanism Greenstick fractures ...
Article

Greig cephalopolysyndactyly syndrome

The Greig cephalopolysyndactyly syndrome (GCPS) is a rare pleiotropic, multiple congenital anomaly syndrome. It is primarily characterized by: polydactyly-polysyndactyly: preaxial polydactyly (most common 2) or mixed pre- and postaxial polydactyly true ocular hypertelorism macrocephaly fro...
Article

Greulich and Pyle method

The Greulich and Pyle method is one of the two main ways to assess the bone age of children.  Both main methods of bone age assessment require a left hand and wrist radiograph. The Greulich and Pyle method makes use of a standard bone age atlas that the reporter can compare their image to and m...
Article

Grey matter heterotopia

The grey matter heterotopias are a relatively common group of conditions characterized by interruption of normal neuronal migration from near the ventricle to the cortex, thus resulting in "normal neurons in abnormal locations" 2. They are a subset of disorders of cortical formation 3-4. Grey m...
Article

Growth arrest lines

Growth arrest lines, also known as growth resumption lines, Harris lines or Park lines, are alternating transverse rings of sclerosis at the metaphysis of a long bone. Pathology The radiographic finding occurs from alternating cycles of osseous growth arrest and growth resumption. This appears...
Article

Gymnast wrist

Gymnast wrist is a term that is used to describe a variety of chronic overuse injuries of the wrist in gymnasts with an immature skeleton. Gymnast wrist comprises a combination of osseous and ligamentous injuries and usually manifests as a chronic Salter-Harris type I fracture of the distal radi...
Article

Hematuria (pediatric)

Hematuria in a child is evaluated differently than in an adult in two main respects: there is a lower likelihood of a malignancy (renal or bladder) causing the hematuria preference is given to nonionizing radiation Pathology Hematuria can be considered in three main forms: "gross" hematuria...
Article

Hemoglobinopathies

A hemoglobinopathy is a genetic disorder which alters the structure of hemoglobin 1. The result is reduced oxygen-carrying capacity of the blood to the tissues, and other sequelae. Clinical presentation Clinical presentation varies, is related to hypoxia, and characteristically includes the fo...
Article

Hemolytic uremic syndrome

Hemolytic uremic syndrome (HUS) is a multisystem thrombotic microangiopathic disease characterized by the triad of renal failure, hemolytic anemia and thrombocytopenia. It is the most common cause of renal failure in infancy and childhood requiring dialysis.  There are two forms of this syndrom...
Article

Hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a non-malignant but often-fatal disorder of immune dysregulation affecting multiple organs. It is also known as macrophage activation syndrome when occurring in the setting of a rheumatologic disorder. Epidemiology It typically affects infants and yo...
Article

Halberd pelvis

A halberd pelvis refers to a pathognomonic appearance of the pelvis seen in metatropic dysplasia, a rare form of spondyloepimetaphyseal dysplasia. hypoplastic ilia with narrow sacrosciatic notches horizontal acetabular roofs with small associated notches superior to their lateral borders prom...
Article

Hand-foot-and-mouth disease

Hand-foot-and-mouth disease is a viral illness that manifests as vesicular eruptions on the hands and feet as well as painful ulcers of the oral mucosa. Symptoms usually resolve spontaneously in 7-10 days. In most cases, there is a prodrome of fever, vomiting, diarrhea, anorexia, and malaise. ...
Article

Hand-foot syndrome (chemotherapy)

Hand-foot syndrome, also known as palmar-plantar erythrodysaesthesia or Burgdorf reaction, is a benign, aseptic, self-limiting complication of many chemotherapeutic agents characterized by a widespread erythema, edema and ulceration of the hands and feet.  Causative drugs Many chemotherapeutic...
Article

Hand-foot syndrome (sickle cell disease)

Hand-foot syndrome, also simply referred to as dactylitis, is a self-limiting manifestation of a vaso-occlusive crisis in individuals with sickle cell anemia. Terminology Dactylitis is not a specific finding in sickle cell disease, therefore cautious usage is advised if one chooses to employ i...
Article

Hand series (pediatric)

The hand series for pediatrics often consist of a posteroanterior and lateral view only in order to minimize radiation dose to the patient. Depending on the department and clinical indication, an additional oblique view may also be done. Indications trauma with suspected fracture suspected di...
Article

Harlequin eye deformity

The harlequin eye deformity is characterized by elevation of the superolateral corner of the orbit. It may be seen in unilateral (plagiocephaly) or bilateral (brachycephaly) coronal suture synostosis. History and etymology The term harlequin eye derives from the appearance of the eyes on a har...
Article

Harrison sulcus

The Harrison sulcus or Harrison groove refers to a groove at the lower end of the rib cage seen in young children/infants with abnormally weak bones (e.g. rickets) or chronic respiratory disease (e.g. severe asthma). The lower chest is drawn in with flaring of the rib margin. The exact cause is ...

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